I’ m tired out. I ______ all afternoon and I don’t seem to have finished anything.

Please keep the secret to , children! Don’t let anybody else know it.

If you don’t make up your mind to get ridof your bad habits，youwon’t be able to_________your goal

In our school library there anumber of books on science and the number of them growinglarger and larger.

ou meet some trouble about how to usethis new kind of machine, you canthe instruction.