37. Gifts/ sets of four/ usually avoided/ because/ it/ considered/ unlucky number.

=>______Gifts in sets of four are usually avoided because it is considered an unlucky number _________.

38. There/also a superstition/ that/ potted plants/ ecourage sickness/ and/ should/ avoided/ as well.

=> __There is also a superstition that potted plants encourage sickness and should be avoided as well.

40. Gifts/ should always/ given/ received/ two hands/ and/ it/ common/ the recipient/ decline/ a gift/ up/ three times/ before/ accepting it.

=> ____________Gifts should always be given and received with two hands and it's the recipient to decline a gift up to three times before accepting it._____________________.

CHÚC BẠN HỌC TỐT !

=>

37. Gifts in sets of four are usually avoided because it is considered an unlucky number.

-> bị động HTĐ is/am/are V3/ed

38. There is also a superstition that potted plants encourage sickness and should be avoided as well.

-> and : và

-> should be V3/ed

-> there is + N số ít

40. Gifts should always be given and received with two hands and it's common for the recipient to decline a gift up to three times before accepting it.

-> bị động should be V3/ed

-> it's common (for sb) to V