1 has improved 2 have.. read 3 finished 4 have ... been 5 have seen 6did ... do 7 visited 8 bought 9 have learned... was 10have just cleaned 11 has already been 12 have never read

1. Has improved (thì htht "recently") 2. Have/read (thì htht "so far") 3. Finished (thì qk đơn "ago") 4. Have/ever been (thì htht) 5. Have seen (thì htht "several times") 6. Did/do (thì qk đơn "last night") 7. Have visted (thì htht "this is the first time") 8. Bought (thì qk đơn "ago") 9. Have learned/was (thì htht "since") 10. Have just cleaned (vì có từ "just", ngoài ra còn có cụm "be careful!": hãy cẩn thận, tức là vừa làm xong tức thì nên là thì htht) 11. Has already been (thì htht) 12. Have never read (thì htht "before") Chúc bạn học tốt nha!!