Open the brackets and put the verbs into the proper lense (the Present Indefinite, the Present Continuous, the Present Perfect Continuous or the Present Perfect Tense)
1. He ( finish) the first past of his book and now he (write) the second. He (work) at his book for two years. 2. Dusliri Hoffman, who (play) the hero, (give) a fine performance. 3. Why your hair (be) wet? You (swim)? 4. Doctors and scientists (show) recently the benefits of fish in the diet.