[ Grammar ]
It is always interesting ——- people in airports while you’re waiting for a flight
A. being observed
B. observe
C. to have observed
D. to observe

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Parts of Speech and GrammarGRAMMAR - Could / Could notSentence StructurePresent TenseTenseModals of Necessity and SuggestionPresent Perfect SimpleGender and GrammarGrammar and StructurePronouns ( Interrogative )Other quiz:
Present Simple & Present Progressive Tense › ViewNhững từ có tận cùng nào phải thêm es?
A. o, s, ch, x, sh, z
B. o, s, ch,r , th
C. S, th, ch, z, x
D. z, x, r, th. ss, xx
Tenses › View
She has forgotten her purse since she was at home.
A. Simple Present Tense
B. Present Continuous Tense
C. Present Perfect Tense
D. Simple Future Tense
Vocabulary › Viewstretched or pulled tight; not loose or slack
A. artillery
B. taut
C. plunge
D. fray
Grammar › View
The cleaner ………… the floor every week.
A. sweeps
B. is sweeping
C. sweep
