[ Infinitive and Gerund ]
It is quite difficult ____________ how they did that.
A. imagine
B. to imagine
C. imagining

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SuperlativesGerund NounBasic GrammarGerund vs InfinitiveEmployment VocabularyCoordinating and Subordinating ConjunctionsJobsConditional Sentences Type 0, 1 and 2Simple Past ContinuosAdjective OrderOther quiz:
Grammar and Vocabulary › View_________ farming is better for the environment because it doesn’t use harmful chemicals.
A. chemistry
B. products
C. environment
D. organic
Vocabulary › View
What does the word ‘decrees’ mean?
A. an infectious disease that causes a high rate of death
B. mischievous
C. energetic
D. to declare a formal order
Grammar › ViewA: I’m going to learn Spanish.
B: Great! Spanish …………. a beautiful language.
A. is
B. are
Phrasal Verb › View
The Covid-19 pandemic reminds us to respect doctors and nurses, who______ others in our society.
A. go on
B. call back
C. pick up
D. care for