Tense system
- Simple, continuous, perfect and perfect continuous in present, past and future.
- Present perfect: has/have + past participle – She has finished.
Time markers
- since/for (perfect), ago (past), already/yet (perfect).
Key idea
Accurate tense use depends on time markers; present perfect (has/have + past participle) links past actions to now.
Remember
Use 'since' with a point in time and 'for' with a length of time.