Using adverb clauses with time expressions

WHEN:

• "at that moment", "at that time",...
• Simpre past or present.

BEFORE:

• "before that moment".
• Simple past or present.

AFTER:

• "after that moment".
• Present for future events.
• Past or past perfect for past events.

WHILE, AS:

• "during that time".
• Indicates an action in progress.
• Past continous.

BY THE TIME:

• It expresses the idea that one event has been completed fefore another.
• Past perfect for past events.
• Future perfect for future events.

UNTIL, TILL:

• "up to that time"
• Till is usually only used in spoken English.
• Simple present or simple past.

SINCE:

• "from that time"
• Present perfect continous.

AS SOON AS:

• "when something happens -immediately afterwards"
• Simple present or present perfect.

WHENEVER, EVERY TIME:

• "each time something happens".
• Simple present or simple past.

THE FIRST, SECOND, LAST TIME,...

• "that specific time"
• we can use these forms to be more specific about which time of a number of times something happened.