UNIT 2 — TRAVEL — Lesson 3B
Time Clauses

The following chart gives you information about the words used in time clauses.

when	describes the first action
	use with the simple past
Example I was packing my suitcase when the travel agent called.
after	describes the first action
	use with the simple past
Example I packed my suitcase after I washed my clothes.
before	describes the second action
	use with the simple past
Example I washed my clothes before I packed my suitcase.
while	describes actions that happen at the same time
	use with the past continuous
Example I was thinking about my holiday while I was packing my suitcase.

It is important to know that before, while, after and when are also used in the present and future.