—Why do you look so puzzled?
—Oh，I ________ over a most difficult maths problem.
A．thoughtB．have thought
C．a(chǎn)m thinkingD．think
C
考查時態(tài)。句意：——為什么你看上去這么困惑？——哦，我正在思考一道數(shù)學(xué)難題。根據(jù)問話者說的“l(fā)ook so puzzled”可知，“思考難題”這一動作正在進(jìn)行當(dāng)中，故選C。
練習(xí)冊系列答案
相關(guān)習(xí)題

科目：高中英語 來源：不詳 題型：單選題

--- What a mess Taylor has made!
--- Yes. I_______ her to do it another way, but she wouldn’t listen.
A．was advisingB．will adviseC．would adviseD．had advised

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

(2013·高考陜西卷)Jim________a late night film at home when，right in the middle of a thrilling scene，the television went blank.
A．watchedB．had watched
C．was watchingD．would be watching

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

(2013·高考天津卷)The water supply has been cut off temporarily because the workers ________ one of the main pipes.
A．had repairedB．have repaired
C．repairedD．a(chǎn)re repairing

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

(2013·高考江蘇卷)I should not have laughed if I________ you were serious.
A．thoughtB．would think
C．had thoughtD．have thought

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

Tom is very happy in China during this period because his Chinese ________ every day.
A．has improvedB．is improving
C．improvedD．is improved

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

(2013·山東，27)—Oh no! We're too late.The train________.
— That's OK.We'll catch the next train to London.
A．was leavingB．had left
C．has leftD．has been leaving

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

If their marketing plans succeed，they ________ their sales by 20 percent.
A．will increaseB．have been increasing
C．have increasedD．would be increasing

查看答案和解析>>

科目：高中英語 來源：不詳 題型：單選題

_______ for many times, he still hopes to win.
A．FailingB．FailedC．Having failedD．To have failed

查看答案和解析>>

同步練習(xí)冊答案