diff --git a/R/available.R b/R/available.R
index 2ad9055..7383b12 100644
--- a/R/available.R
+++ b/R/available.R
@@ -10,7 +10,7 @@
 #' @return A logical indicates FAERS can have data for the `years` and
 #' `quarters` required?
 #' @examples
-#' faers_available(c(2011, 2023), c("q1", "q2"))
+#'  faers_available(c(2011, 2023), c("q1", "q2"))
 #' @export
 faers_available <- function(years, quarters, force = FALSE, internal = FALSE) {
     assert_inclusive(quarters, faers_file_quarters)
diff --git a/R/combine.R b/R/combine.R
index a094cbe..3c4ee82 100644
--- a/R/combine.R
+++ b/R/combine.R
@@ -5,11 +5,16 @@
 #' @param x A list of [FAERSxml] or [FAERSascii] objects.
 #' @return A [FAERSxml] or [FAERSascii] object.
 #' @examples
-#' \donttest{
-#' data1 <- faers(2004, "q1")
-#' data2 <- faers(2004, "q2")
+#' # the files included in the package are sampled
+#' data1 <- faers_parse(
+#'     system.file("extdata", "aers_ascii_2004q1.zip", package = "faers"),
+#'     compress_dir = tempdir()
+#' )
+#' data2 <- faers_parse(
+#'     system.file("extdata", "faers_ascii_2017q2.zip", package = "faers"),
+#'     compress_dir = tempdir()
+#' )
 #' faers_combine(list(data1, data2))
-#' }
 #' @export
 faers_combine <- function(x) {
     assert_(x, is.list, "a list")
diff --git a/R/dedup.R b/R/dedup.R
index c23fab3..46165d1 100644
--- a/R/dedup.R
+++ b/R/dedup.R
@@ -2,12 +2,17 @@
 #' @param object A [FAERSascii] object.
 #' @param ... Other arguments passed to specific methods.
 #' @return A [FAERSascii] object.
-#' @examples 
+#' @seealso [faers_standardize]
+#' @examples
 #' \dontrun{
-#'  data <- faers(2004, c("q1", "q2"))
-#'  # you should replace `meddra_path` with yours
-#'  data <- faers_standardize(data, meddra_path)
-#'  faers_dedup(data)
+#' # you must change `dir`, as the files included in the package are sampled
+#' data <- faers(c(2004, 2017), c("q1", "q2"),
+#'     dir = system.file("extdata", package = "faers")
+#' )
+#' # we must standardize firstly
+#' # you should replace `meddra_path` with yours
+#' data <- faers_standardize(data, meddra_path)
+#' faers_dedup(data)
 #' }
 #' @export
 #' @name faers_dedup
diff --git a/R/download.R b/R/download.R
index fe5e435..4c4ab9e 100644
--- a/R/download.R
+++ b/R/download.R
@@ -11,9 +11,12 @@
 #'  [new_handle][curl::new_handle].
 #' @return An atomic character for the path of downloaded files.
 #' @examples
-#' \donttest{
-#' faers_download(year = 2004, quarter = "q1", dir = tempdir())
-#' }
+#' # you must change `dir`, as the file included in the package is sampled
+#' # in this way, the file will downloaded from FAERS
+#' faers_download(
+#'     year = 2004, quarter = "q1",
+#'     dir = system.file("extdata", package = "faers")
+#' )
 #' @export
 faers_download <- function(years, quarters, format = NULL, dir = getwd(), ...) {
     format <- match.arg(format, faers_file_format)
diff --git a/R/faers.R b/R/faers.R
index 1c47884..7dced57 100644
--- a/R/faers.R
+++ b/R/faers.R
@@ -4,10 +4,9 @@
 #' @param handle_opts Extra handle options passed to each request
 #' [new_handle][curl::new_handle].
 #' @return A [FAERSxml] or [FAERSascii] object.
-#' @examples 
-#' \donttest{
-#'  data <- faers(2004, "q1")
-#' }
+#' @examples
+#' # you must change `dir`, as the file included in the package is sampled
+#' data <- faers(2004, "q1", dir = system.file("extdata", package = "faers"))
 #' @export
 faers <- function(years, quarters, format = NULL, dir = getwd(), compress_dir = dir, handle_opts = list()) {
     format <- match.arg(format, faers_file_format)
diff --git a/R/merge.R b/R/merge.R
index 03a4173..62065fc 100644
--- a/R/merge.R
+++ b/R/merge.R
@@ -12,11 +12,10 @@
 #'
 #' @return A [data.table][data.table::data.table] object.
 #' @examples 
-#' \donttest{
-#'  data <- faers(2004, "q1")
-#'  faers_merge(data, "indi")
+#'  # you must change `dir`, as the file included in the package is sampled
+#'  data <- faers(2004, "q1", dir = system.file("extdata", package = "faers"))
+#'  faers_merge(data, "indi") # only one field is just like faers_get()
 #'  faers_merge(data, c("demo", "indi"))
-#' }
 #' @export
 #' @name faers_merge
 methods::setGeneric("faers_merge", function(object, ...) {
diff --git a/R/methods-utils.R b/R/methods-utils.R
index daebe8f..08fa564 100644
--- a/R/methods-utils.R
+++ b/R/methods-utils.R
@@ -25,8 +25,8 @@
 #'    `faers_keep` to filter.
 #' @export
 #' @examples 
-#' \donttest{
-#'  data <- faers(2004, "q1")
+#'  # you must change `dir`, as the file included in the package is sampled
+#'  data <- faers(2004, "q1", dir = system.file("extdata", package = "faers"))
 #'  faers_get(data, "indi")
 #'  data[["indi"]]
 #'  faers_get(data, "demo")
@@ -34,7 +34,6 @@
 #'  faers_mget(data, c("indi", "drug"))
 #'  faers_mget(data, c("indi", "demo"))
 #'  faers_primaryid(data)
-#' }
 #' @rdname FAERS-methods
 methods::setGeneric("faers_get", function(object, ...) {
     methods::makeStandardGeneric("faers_get")
diff --git a/R/parse.R b/R/parse.R
index 933bb37..ec08017 100644
--- a/R/parse.R
+++ b/R/parse.R
@@ -11,6 +11,12 @@
 #' @param compress_dir A string specifies the directory to extract files to. It
 #' will be created if necessary.
 #' @return A [FAERSxml] or [FAERSascii] object.
+#' @examples 
+#' # the files included in the package are sampled
+#' data <- faers_parse(
+#'     system.file("extdata", "aers_ascii_2004q1.zip", package = "faers"),
+#'     compress_dir = tempdir()
+#' )
 #' @export
 faers_parse <- function(path, format = NULL, year = NULL, quarter = NULL, compress_dir = getwd()) {
     assert_string(path, empty_ok = FALSE)
diff --git a/R/standardize.R b/R/standardize.R
index ca6d068..0ed97c1 100644
--- a/R/standardize.R
+++ b/R/standardize.R
@@ -6,9 +6,12 @@
 #' <https://www.meddra.org/>
 #' @examples 
 #' \dontrun{
-#'  data <- faers(2004, "q1")
+#' #' # you must change `dir`, as the files included in the package are sampled
+#' data <- faers(c(2004, 2017), c("q1", "q2"),
+#'     dir = system.file("extdata", package = "faers")
+#' )
 #' # you should replace `meddra_path` with yours
-#'  data <- faers_standardize(data, meddra_path)
+#' data <- faers_standardize(data, meddra_path)
 #' }
 #' @export
 #' @name faers_standardize
diff --git a/man/FAERS-methods.Rd b/man/FAERS-methods.Rd
index 4405f9e..1648238 100644
--- a/man/FAERS-methods.Rd
+++ b/man/FAERS-methods.Rd
@@ -102,8 +102,8 @@ better to run \link[=FAERS]{faers}.
 }
 }
 \examples{
-\donttest{
- data <- faers(2004, "q1")
+ # you must change `dir`, as the file included in the package is sampled
+ data <- faers(2004, "q1", dir = system.file("extdata", package = "faers"))
  faers_get(data, "indi")
  data[["indi"]]
  faers_get(data, "demo")
@@ -112,4 +112,3 @@ better to run \link[=FAERS]{faers}.
  faers_mget(data, c("indi", "demo"))
  faers_primaryid(data)
 }
-}
diff --git a/man/faers.Rd b/man/faers.Rd
index eabfffe..3fe75d0 100644
--- a/man/faers.Rd
+++ b/man/faers.Rd
@@ -38,7 +38,6 @@ A \link{FAERSxml} or \link{FAERSascii} object.
 Download and parse FAERS Quarterly Data files
 }
 \examples{
-\donttest{
- data <- faers(2004, "q1")
-}
+# you must change `dir`, as the file included in the package is sampled
+data <- faers(2004, "q1", dir = system.file("extdata", package = "faers"))
 }
diff --git a/man/faers_available.Rd b/man/faers_available.Rd
index 5d88a38..3000526 100644
--- a/man/faers_available.Rd
+++ b/man/faers_available.Rd
@@ -28,5 +28,5 @@ This function check if data for the years and quarters selected are
 available at FAERS to be downloaded.
 }
 \examples{
-faers_available(c(2011, 2023), c("q1", "q2"))
+ faers_available(c(2011, 2023), c("q1", "q2"))
 }
diff --git a/man/faers_combine.Rd b/man/faers_combine.Rd
index 466710e..f7684cf 100644
--- a/man/faers_combine.Rd
+++ b/man/faers_combine.Rd
@@ -17,9 +17,14 @@ Packed all \link{FAERSascii} or \link{FAERSxml} objects into a single \link{FAER
 \link{FAERSxml} object
 }
 \examples{
-\donttest{
-data1 <- faers(2004, "q1")
-data2 <- faers(2004, "q2")
+# the files included in the package are sampled
+data1 <- faers_parse(
+    system.file("extdata", "aers_ascii_2004q1.zip", package = "faers"),
+    compress_dir = tempdir()
+)
+data2 <- faers_parse(
+    system.file("extdata", "faers_ascii_2017q2.zip", package = "faers"),
+    compress_dir = tempdir()
+)
 faers_combine(list(data1, data2))
 }
-}
diff --git a/man/faers_dedup.Rd b/man/faers_dedup.Rd
index f0d3514..4022863 100644
--- a/man/faers_dedup.Rd
+++ b/man/faers_dedup.Rd
@@ -31,9 +31,16 @@ Tidy up FAERS Quarterly Data with duplicate records removed
 }
 \examples{
 \dontrun{
- data <- faers(2004, c("q1", "q2"))
- # you should replace `meddra_path` with yours
- data <- faers_standardize(data, meddra_path)
- faers_dedup(data)
+# you must change `dir`, as the files included in the package are sampled
+data <- faers(c(2004, 2017), c("q1", "q2"),
+    dir = system.file("extdata", package = "faers")
+)
+# we must standardize firstly
+# you should replace `meddra_path` with yours
+data <- faers_standardize(data, meddra_path)
+faers_dedup(data)
 }
 }
+\seealso{
+\link{faers_standardize}
+}
diff --git a/man/faers_download.Rd b/man/faers_download.Rd
index 7984757..e695a44 100644
--- a/man/faers_download.Rd
+++ b/man/faers_download.Rd
@@ -28,7 +28,10 @@ An atomic character for the path of downloaded files.
 This function downloads the FAERS data for selected years and quarters.
 }
 \examples{
-\donttest{
-faers_download(year = 2004, quarter = "q1", dir = tempdir())
-}
+# you must change `dir`, as the file included in the package is sampled
+# in this way, the file will downloaded from FAERS
+faers_download(
+    year = 2004, quarter = "q1",
+    dir = system.file("extdata", package = "faers")
+)
 }
diff --git a/man/faers_merge.Rd b/man/faers_merge.Rd
index 4679d3b..455d97e 100644
--- a/man/faers_merge.Rd
+++ b/man/faers_merge.Rd
@@ -26,11 +26,10 @@ faers_merge(object, ...)
 \item{all}{logical; \code{all = TRUE} is shorthand to save setting both
 \code{all.x = TRUE} and \code{all.y = TRUE}.}
 
-\item{all.x}{logical; if \code{TRUE}, then extra rows will be added to the
-output, one for each row in \code{x} that has no matching row in \code{y}.
-These rows will have 'NA's in those columns that are usually filled with values
-from \code{y}.  The default is \code{FALSE}, so that only rows with data from both
-\code{x} and \code{y} are included in the output.}
+\item{all.x}{logical; if \code{TRUE}, rows from \code{x} which have no matching row
+in \code{y} are included. These rows will have 'NA's in the columns that are usually
+filled with values from \code{y}. The default is \code{FALSE} so that only rows with
+data from both \code{x} and \code{y} are included in the output.}
 
 \item{all.y}{logical; analogous to \code{all.x} above.}
 }
@@ -54,9 +53,8 @@ You'd better only merge necessary data, otherwise a lot of memory will
 be consumed to merge all fields data.
 }
 \examples{
-\donttest{
- data <- faers(2004, "q1")
- faers_merge(data, "indi")
+ # you must change `dir`, as the file included in the package is sampled
+ data <- faers(2004, "q1", dir = system.file("extdata", package = "faers"))
+ faers_merge(data, "indi") # only one field is just like faers_get()
  faers_merge(data, c("demo", "indi"))
 }
-}
diff --git a/man/faers_parse.Rd b/man/faers_parse.Rd
index 6e2abc2..80e7cf8 100644
--- a/man/faers_parse.Rd
+++ b/man/faers_parse.Rd
@@ -36,3 +36,10 @@ A \link{FAERSxml} or \link{FAERSascii} object.
 \description{
 Parse FAERS Quarterly Data
 }
+\examples{
+# the files included in the package are sampled
+data <- faers_parse(
+    system.file("extdata", "aers_ascii_2004q1.zip", package = "faers"),
+    compress_dir = tempdir()
+)
+}
diff --git a/man/faers_standardize.Rd b/man/faers_standardize.Rd
index 45baaf5..9d354bd 100644
--- a/man/faers_standardize.Rd
+++ b/man/faers_standardize.Rd
@@ -24,9 +24,12 @@ Standardize FAERS Quarterly Data for Preferred Term and drug names
 }
 \examples{
 \dontrun{
- data <- faers(2004, "q1")
+#' # you must change `dir`, as the files included in the package are sampled
+data <- faers(c(2004, 2017), c("q1", "q2"),
+    dir = system.file("extdata", package = "faers")
+)
 # you should replace `meddra_path` with yours
- data <- faers_standardize(data, meddra_path)
+data <- faers_standardize(data, meddra_path)
 }
 }
 \seealso{