I (A) spent two days (B) to finsh (C) the model (D) of a stilt house
=> B ; finish --> finishing
Athough (A) it rained (B) heavily (C) but they still (D) went camping
=> C; bỏ but
She said she (A) will work (B) for a (C) charitable organization ​when she (D) grew up
=> A; will --> would
They (A) are working very (B) hardly (C) to prepare (D) for the new project.
--> B ; hardly --> hard
(A) The students (B) in my class (C) are looking forward (D) to hold mid-autumn festival
=> D ; hold --> holding