Future time clauses: when, until, once and as soon as

The idea

In ordinary future time clauses, use present forms after when, before, after, until, once and as soon as. Present perfect can highlight completion: once you have checked. The main clause may use will, another modal or an imperative.

Examples

• As soon as the glue dries, I'll attach the hooks.
• We won't open the boxes until Mina arrives.
• Once you have checked the measurements, you can cut the cloth.
• Please close the gate before you leave.
• I'll wash the brushes after I finish painting.
• When will the ferry return?

Watch out

Do not add future will just because the time clause refers to tomorrow. Direct questions such as When will the ferry return? use a different structure. Present perfect is not always obligatory; once you check can also be appropriate.

Try it yourself

1. Choose the correct option. As soon as the glue ___, I'll attach the hooks. (dries / will dry)

   Show answer or example answer

   dries

   As soon as introduces the future time clause, so use present dries, not future will dry.

2. Choose the correct option. We won't open the boxes until Mina ___. (arrives / will arrive)

   Show answer or example answer

   arrives

   After time conjunction until, use present arrives. The future meaning is supplied by the whole context.

3. Choose the correct option. Once you ___ the measurements, you can cut the cloth. (have checked / will have checked)

   Show answer or example answer

   have checked

   Have checked is present perfect in a future time clause. It highlights completing the check before cutting.

Use it today

Plan three steps of a practical task using before, after and once. Identify the time clause in each sentence and choose present simple or present perfect according to your focus.