Definite & indefinite articles

根據以上段落, 點解 javelin, shot put, discus 前面加 the. 但是,
running races 前面冇加articles. 還有, slow bicycle race 前面加 a ??
而 第二次提到 slow bicycle race 點解唔係加 the ??

Javelin <--- is a countable noun.
It is wrong to say " javelin"( no article) or " a javelin".
The javelin = It refers to the sports EVENT.
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We had running raceS and a slow bicycle race. ( To talk about running RACES and a slow bicycle race in gerneral, we do not need
the definite article" the".)
Example:
We have exhibitions and a talent show at our school every year.
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Well, in a slow bicycle race the winner is the person who cycles the slowest!
( This is what a slow bicycle race is all about.)
You are NOT describing THE slow bicycle race here. ( If so, do use" the".)

You are only telling people what A SLOW bicycle race is , so you do not need to change "a" to "the".

根據以上段落, 點解 javelin, shot put, discus 前面加 the.
Ans. : 'the'係呢到加同唔加都得。

running races 前面冇加articles.
Ans. : 因為有好多種, 而唔係一種, 理應唔加。
slow bicycle race 前面加 a ??
Ans. : 因為唔知係邊種, 係某一種, 所以用'a'。

第二次提到 slow bicycle race 點解唔係加 the ??
Ans. : 如果你之前已說明係mac, 之後提這種race就應該用'the', 如果之前無提過或說明過, 這裡只說某一種'slow bicycle race'(可能暗示有其他種類的'slow bicycle race')。