什么是FOR TO DO語句的變量和循環
這東西沒必要解釋的吧。
for i := 5 to 10 do
writeln(i);
這個展開就是
i:= 5;
writeln(i);
i:= 6;
writeln(i);
。.
i:= 10;
writeln(i);
pascal里的for循環,循環變量一定是每次增1或減1的。
to/downto 左邊是初值,右邊是終值,to的話就是+1,downto就是-1
用begin..end包裹,那是表示一個語句塊,因為按規定for語句后只能有一條執行語句,當有多條語句的時候就必須有begin。end來包裹這些語句。
for sb to do sth可用作哪些句子成分
for sb to do sth結構為for加名詞或代詞賓格再加不定式構成的復合結構,它在句子中可以用作以下句子成分: 一、用作主語。
如: for sb to do sth結構在句子中可以用作主語。如: For you to ask Joe would be a big mistake. 你要是去問喬,那將是一大錯誤。
For Ann to go to France would make me very happy. 安要是到法國去將使我感到很高興。 二、用作表語。
如: for sb to do sth結構有時可用作表語。如: It is for you to decide. 該由你來決定。
His idea is for us to travel in separate cars. 他的意思是我們不要同乘一輛汽車。 There's a plan for Jack to spend a year in Japan. 有一個計劃是讓杰克在日本呆上一年。
三、用作賓語。如: for sb to do sth結構有時也可用作某些動詞的賓語。
如: She hates for people to feel sad. 她不愿看到人們憂心忡忡。 I thought it strange for her to be out so late. 她這么晚還不回來,我覺得有些奇怪。
I would like for you to stay as long as you want. 我希望你留下來,想留多久就留多久。 四、用作定語。
如: for sb to do sth結構用可以作定語。如: It's time for everybody to go to bed. 是大家睡覺的時候了。
He raised his arm as a signal for us to stop. 他抬起手臂示意我們停下。 五、用作狀語。
如: for sb to do sth結構可以用作狀語。如(): We were all shouting for him to shoot. 我們都喊著要他射門。
(表目的) This is much too heavy for you to lift. 這東西太重,你拿不起來。(表結果) How would it do for me to write to him? 我來給他寫信如何?(表條件) ~。