Present perfect + for-since or present perfect continuous

Present perfect + for-since or present perfect continuous
Present perfect + for-since or present perfect continuous

คำแนะนำของผู้เขียน

Correct mistakes and make sentences using present perfect or present perfect continuous

สำรวจแผ่นงาน

Zero, first and second conditional

Grammar - ESL

conditional: zero, first and second structure, exercises

Grammar test 124

Grammar - ESL

grammar test

Grammar modals

Grammar - ESL

Could
We can use could + infinitive to talk about a general possibility in the past (compare with the use of 'can' above):
Prices could be high in the sixteenth century.
This is not used to talk about specific possibilites in the past (instead we use could + have + past participle):
He could have been working late (not: 'could be'. As this is a specific possiblity, 'could be' is present tense)

Grammar test 124

Grammar - ESL

grammar test