R and d program
[经] 研究与发展, 开发规划
🧩 词语组成解析
and
[ənd, ən,ænd]
conj. 和，与;而且;于是，然后;因此;
🗣️ 情景例句
Oh, who could that be?
啊，这会是谁呢？
They had to cut down a lot of trees to make room for farms.
他们为了为农场增加空间不得不砍倒很多树。
His few material possessions make it possible for him to move from place to place with ease.
他几乎没有什么财产，这使他能够轻松自如地在各地奔波。