—Students should try to do a little studying every evening throughout the term, rather than study all night

during the week before the exam.  

—Exactly. ____________.[ ]

A. Practice makes perfect                

B. The early bird catches the worm

C. Slow but sure wins the race        

D. Delays are dangerous

哈钦松、塔赫他间和克朗奎斯特等人是单元说的主要代表，他们认为现代被子植物来自一个（）植物，而（）类，特别是其中的（）目比较接近（）植物，有可能就是它们的直接后裔。