PPT预览
Language Points 1.l don't think you can find one unless you have a bigger telescope.我认为你发现不了星星,除非你有一个大点的望远镜。 unless,连词,意为“除非,如果不”,引导条件状语从句,相当于if...not... lwill go for a picnic unless it rains tomorrow.如果明天不下雨,我就去野餐。 One can not learn a language well unless one works hard.学好一种语言非下苦功不可。