diff --git a/R/backend-dbplyr__duckdb_connection.R b/R/backend-dbplyr__duckdb_connection.R
index a36bf377a..25c1e262c 100644
--- a/R/backend-dbplyr__duckdb_connection.R
+++ b/R/backend-dbplyr__duckdb_connection.R
@@ -275,10 +275,10 @@ sql_translation.duckdb_connection <- function(con) {
 
       # clock
       add_days = function(x, n, ...) {
-        build_sql("DATE_ADD(", !!x, ", INTERVAL '", n ," day')")
+        build_sql("DATE_ADD(", !!x, ", INTERVAL (", n ,") day)")
       },
       add_years = function(x, n, ...) {
-        build_sql("DATE_ADD(", !!x, ", INTERVAL '", n ," year')")
+        build_sql("DATE_ADD(", !!x, ", INTERVAL (", n ,") year)")
       },
       get_year = function(x) {
         build_sql("DATE_PART('year', ", !!x, ")")
@@ -302,6 +302,17 @@ sql_translation.duckdb_connection <- function(con) {
         build_sql("DATEDIFF('day', ", !!start, ", " ,!!end, ")")
 
       },
+      date_build = function(year, month = 1L, day = 1L, ..., invalid = NULL) {
+        dbplyr:::check_unsupported_arg(invalid, allow_null = TRUE)
+        rlang::check_dots_empty()
+        build_sql("MAKE_DATE(CAST(", year, " AS INTEGER), CAST(", month, " AS INTEGER), CAST(", day, " AS INTEGER))")
+
+      },
+      difftime = function(time1, time2, tz, units = "days") {
+        dbplyr:::check_unsupported_arg(tz)
+        dbplyr:::check_unsupported_arg(units, allowed = "days")
+        build_sql("DATEDIFF('day', ", !!time2, ", " ,!!time1, ")")
+      },
 
       # stringr functions
       str_c = sql_paste(""),
diff --git a/tests/testthat/test-backend-dbplyr__duckdb_connection.R b/tests/testthat/test-backend-dbplyr__duckdb_connection.R
index 0a4435c1e..c2ef68d42 100644
--- a/tests/testthat/test-backend-dbplyr__duckdb_connection.R
+++ b/tests/testthat/test-backend-dbplyr__duckdb_connection.R
@@ -141,11 +141,12 @@ test_that("custom clock functions translated correctly", {
   translate <- function(...) dbplyr::translate_sql(..., con = con)
   sql <- function(...) dbplyr::sql(...)
 
-  expect_equal(translate(add_days(x, 1L)), sql(r"{DATE_ADD(x, INTERVAL '1 day')}"))
-  expect_equal(translate(add_days(x, 2L)), sql(r"{DATE_ADD(x, INTERVAL '2 day')}"))
+  m <- 1
+  expect_equal(translate(add_days(x, m)), sql(r"{DATE_ADD(x, INTERVAL (m) day)}"))
+  expect_equal(translate(add_days(x, 2L)), sql(r"{DATE_ADD(x, INTERVAL (2) day)}"))
 
-  expect_equal(translate(add_years(x, 1L)), sql(r"{DATE_ADD(x, INTERVAL '1 year')}"))
-  expect_equal(translate(add_years(x, 2L)), sql(r"{DATE_ADD(x, INTERVAL '2 year')}"))
+  expect_equal(translate(add_years(x, m)), sql(r"{DATE_ADD(x, INTERVAL (m) year)}"))
+  expect_equal(translate(add_years(x, 2L)), sql(r"{DATE_ADD(x, INTERVAL (2) year)}"))
 
   expect_equal(translate(get_day(x)), sql(r"{DATE_PART('day', x)}"))
   expect_equal(translate(get_month(x)), sql(r"{DATE_PART('month', x)}"))
@@ -156,6 +157,10 @@ test_that("custom clock functions translated correctly", {
                                             precision = "day")),
                sql(r"{DATEDIFF('day', start, end)}"))
 
+  expect_equal(translate(difftime(time1 = "time1", time2 = "time2", units = "days")), sql(r"{DATEDIFF('day', time2, time1)}"))
+  expect_equal(translate(date_build(year = 2000, month = 08, day = 08)), sql(r"{MAKE_DATE(CAST(2000.0 AS INTEGER), CAST(8.0 AS INTEGER), CAST(8.0 AS INTEGER))}"))
+  expect_equal(translate(date_build(year = 2000)), sql(r"{MAKE_DATE(CAST(2000.0 AS INTEGER), CAST(1 AS INTEGER), CAST(1 AS INTEGER))}"))
+
   test_data <- data.frame(
     person = 1L,
     date_1 = as.Date("2000-01-01"),
@@ -197,6 +202,9 @@ test_that("custom clock functions translated correctly", {
                                             precision = "day",
                                             n = 5)))
 
+  expect_error(translate(date_build(year = 2000, month = 08, day = 08, invalid = "next-day")))
+  expect_error(translate(difftime(time1, time2, units = "secs")))
+  expect_error(translate(difftime(time1, time2, tz = Sys.timezone())))
 })
 
 # stringr functions