unit 3 amazing people ⅰ.单项填空 1．i know that when he looks at his watch，it's a ________for us to start the attack. a．sign b．expression c．meaning d．signal 答案 d [句意：我知道当他看手表的时候就是要我们开始进攻的信号。signal信号，符合题意。] 2．now a lot of new technologies can ________problems in industry. a．be applied to solve b．be applied to solving c．apply to solve d．apply to solving 答案 b [考查动词搭配。apply...to...表示“把……应用到……
