21.accident n.

22.by accident

23.accidental adj.

24.accidentally adv.

25.accommodation n.

26.accompany v.

27.according to prep.

28.account n., v.

29.accurate adj.

30.accurately adv.

31.accuse v.

32.achieve v.

33.achievement n.

34.acid n.

35.acknowledge v.

36.acquire v.

37.across adv., prep.

38.act n., v.

39.action n.

40.take action