[ Modals ]
Using lasers to produce extremely short and repeatable pulses of light, today scientists ———— events happening in time intervals as short as l.000 trillionth of a second.
A. must have measured
B. were measuring
C. used to measure
D. may have measured
E. are able to measure
Select your answer:
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Adverbs of TimePossesive Pronouns and Modals of AbilityRelative ClauseCoordinate ConjunctionConditionalPresent Simple PassiveArticle & PrepositionModals of AdviceArticles & PrepositionOther quiz:
Simple Past Tense › ViewI ……….. an monkey last night
A. drawn
B. draw
C. drew
Time › View
What time is it?
07:15
A. A half past seven
B. A quarter past seven
C. A quarter to seven
D. Fifteen to seven