Question

[Tăng Huyền Thương]

1.In 1709, Cristofori worked out .............this could be done successfully, and the piano ............ was born.

2.The piano quickly became extremely popular, and improvements continued to be ................... to it.

3.Tea leaves are then sent to a rolling machine,................ breaks the leaf cells and releases oils which give the tea its flavour. Then, the leaves are left to absorb oxygen and they turn ............. bright copper colour before being heated in an oven and turning black.

4.In the Greek method, the mature fruit are put in brine for .............. to six months, ............being left in the open air to give ................. back their dark colour.