A fruit is the part of a plant that has seeds and flesh (edible covering). A fruit is normally sweet (or sometimes sour) and can be eaten in its raw (uncooked) state. Fruit are the way plants disseminate their seeds.

水果是有种子和果肉的植物的一部分。有的水果是甜的，有的是酸的，可以生吃。水果是植物传播种子的方式。

Grammatically, do you say Fruit or Fruits? 到底加不加“S

The word Fruit is a noun. The word is an exception where the noun is both countable and uncountable. So the plural of Fruit can be either Fruit OR Fruits.

“Fruit”是个名词。这个词既是可数名词也是不可数名词。因此“Fruit”的复数可以是“Fruit”也可以是"Fruits"。

When we think of Fruit as a group collectively and in a non-specific way, then we tend to use the word Fruit (without S).

如果并不特指，而是看做一个整体，我们通常用“Fruit”。

If you are emphasising the different kinds of fruit, then you can use fruits.

如果你想强调水果的不同种类，就可以用“fruits”。

• Would you like some fruit?   你想吃点水果吗？

• There isn't much fresh fruit available in winter.   冬天没有太多新鲜水果。

• The juice is made from a variety of fresh fruits.   果汁是用不同种类的

• avocado - the plural is avocados though you may see avocadoes (less frequently). 牛油果—复数形式是avocados或avocadoes（少见）

• boysenberry - is a cross between a raspberry and a blackberry   博伊森莓—树莓和黑莓的杂交品种

• kiwifruit - sometimes written as two words kiwi fruit. It has the same form in singular and plural kiwifruit.猕猴桃—有时写成两个单词kiwi fruit，单复数同形。

• lychee - sometimes called litchi in US English   荔枝—美国英语有时候也叫litchi。

• mango - the plural of mango can be either mangos or mangoes.   芒果—复数是mangos或mangoes。

• melon - the generic name for most types of melon   甜瓜—多数种类甜瓜的统称

• nectarine - the same a peach but without fur on its skin   油桃—跟桃子一样，但没有毛

• papaya - In some countries it is called pawpaw.   木瓜—在一些国家叫做pawpaw。

• passion fruit - In United States it is written as two words while in some countries it is written as one word: passionfruit. The plural of passion fruit is either passion fruit or passion fruits. 

百香果—在美国，通常写成两个单词passion fruit，但在其他一些国家，写成一个单词passionfruit。复数是passion fruit或passion fruits。

• peach - same as a nectarine but with a slight fur on its skin   桃子—跟油桃一样，但表皮有一些毛。

• banana   香蕉         • blackberry   黑莓       • blackcurrant   黑醋栗

• blueberry   蓝莓      • cherry   樱桃             • coconut   椰子

• fig   无花果             • grape   葡萄              • grapefruit   西柚

• lemon   柠檬           • lime   酸橙               • mandarin   柑橘

• orange   橘子          • pear   梨                  • pomegranate   石榴

• pineapple   菠萝      • plum   李子              • raspberry   树莓

• quince   温柏           • watermelon   西瓜     • strawberry   草莓

Fruits that people think are Vegetables   一些人们误认为是蔬菜的水果

The following are actually fruits in a botanical sense, though are commonly thought of as vegetables due to their culinary uses:

以下的几个在植物学意义上是水果，但通常用于烹饪，人们认为他们是蔬菜。

avocado, cucumber, eggplant, green beans, peppers, pumpkin, squash, tomato, zucchini

鳄梨，黄瓜，茄子，四季豆，辣椒，南瓜，南瓜，番茄，西葫芦

Yes, that's right, the so called vegetables above are in reality fruit, not vegetables.

实际上，他们是水果，并不是蔬菜。

A piece of fruit

We often say a piece of fruit when we refer to one fruit (one apple, one orange etc) without specifying which one it is.

当我们提到一个水果（一个苹果、一个橘子等），但并没有具体指代哪个时，就可以说a piece of fruit。

• She always has a piece of fruit with her breakfast.   她早餐通常会吃一个水果。

The fruit of something

The fruit (or fruits) of something is an expression which means the good results that you obtain from something such as hard work.

The fruit of something的含义是从某件事（如努力工作）中获得的好的结果。

• The award he received is the fruit of his hard work and always trying to do his best.

这个奖项是他努力工作合总是尽最大努力的结果。