$1.$ The house was so expensive that nobody can buy it.
→ S + be + so + adj + that + S + V.
$2.$ It was such cold water that the children couldn't swim in it.
→ S + V + such + a + adjective + singular count noun + that + S + V.
$3.$ Tom has been playing the piano 4 years ago.
→ Thì HTHTTD: S + have/has + been + V-ing
$4.$ Jack and Jill started to learn to drive 2 weeks ago.
→ start to do tức là sắp sửa bắt đầu làm một việc gì đó. Vẫn đang trong giai đoạn chuẩn bị vẫn chưa xong