____ is the letter from—It’s from Mike, my pen pal.

What should I do to learn English well asa beginner— ______, you should memorize some words.

________ fails to realize the importance of improving the learning strategies will have great difficulty in learning.

The Yellow River____________ flood large areas, but now the waters of it are used to_______ energy.

下列词语没有错别字的一项是(　　)