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B1+ Upper-intermediate · GRAMMAR LESSONS

Unit 20: Past modal verbs of deduction

2 exercises · 20 original questions

CEFRA1—C2Every level · Every skill
UNIT 20: PAST MODAL VERBS OF DEDUCTIONQuestion 1 / 20
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GRAMMAR · B1+
Exercise 1 · Exercise 1

Choose the best answer.

Nobody knows exactly why he died. But we think it ___ been an accident.