好老师总是供不应求。
Good teachers are always ___in ___demand.
许多商品没有需求,因为每个家庭都生产自己的商品。
Many goods are not ___in ___demand because each family produces its own goods.
熟练的数据科学家在各个行业都很抢手。
Skilled data scientists are ___in ___demand across various industries.