【C17】A．examineB．checkC．inspectD．investigate

【C19】A．examineB．discoverC．findD．investigate

The scientists began to accumulate data.A．collectB．handleC．analyzeD．investigate

The scientists began to accumulate data.A．collectB．handleC．analyzeD．investigate

【C15】A．suspectB．expectationC．inspectD．respect

【C4】A．perceiverB．receiverC．supervisorD．investigator

The problem was so complicated that Mr. Smith had to______his brains.A．crackB．checkC．rackD