Once Is Not Enough

（原始内容存档于2013年4月27日）.  Entertainment Weekly: "'Once' a Hero". 2007年7月14日 [2008年2月16日]. （原始内容存档于2012年5月9日）.  艾瑞克·派德森. Once Is Not Enough: Summer's Secret Smash - Interview

见Raussen 2013，第21頁，摘录如下：“For Grothendieck it was very clear: he once told me that mathematics is not a competition sport. Mathematicians are different and some

The material must be presented at just the right time; if you are not sleepy enough, the material will wake you up, and if you're deeply asleep, the materials

该多好)等。如果主句是将来时，条件状语从句用一般现在时表示。 unless的意义相当于"if...not"，而且语气较强，一般不用于虚拟语气. e.g. I'll buy a computer if I am able to save up enough money. Unless the weather was bad,my

challenge is achieving a high enough mass-ratio to carry sufficient propellant to achieve orbit, plus a meaningful payload weight. One possibility is to give