Add 什么时候做及物动词用，什么时候做不及物动词用（add to) ?

Add 什么时候做及物动词用，什么时候做不及物动词用（add to) ?

add
added adding adds
Verb
make an addition (to); join or combine or unite with others; increase the quality, quantity, zise or scope of; "We added two students to that dorm room"; "She added a personal note to her letter"; "Add insult to injury"; "Add some extra plates to the dinner table"
(antonym) take away, take out
(hypernym) increase
(hyponym) modify, qualify
(derivation) addition
state or say further; "`It doesn't matter,' he supplied"
(synonym) append, supply
(hypernym) state, say, tell
(hyponym) slip in, stick in, sneak in, insert
bestow a quality on; "Her presence lends a certain cachet to the company"; "The music added a lot to the play"; "She brings a special atmosphere to our meetings"; "This adds a light note to the program"
(synonym) lend, impart, bestow, contribute, bring
(hypernym) change, alter, modify
(hyponym) instill, transfuse
(derivation) addition, add-on, improver
make an addition by combining numbers; "Add 27 and 49, please!"
(synonym) add together
(antonym) subtract, deduct, take off
(hypernym) calculate, cipher, cypher, compute, work out, reckon, figure
(hyponym) foot, foot up
(see-also) total, number, add up, come, amount
(verb-group) total, tot, tot up, sum, sum up, summate, tote up, add together, tally, add up
(derivation) summation, addition, plus
(classification) arithmetic
determine the sum of; "Add all the people in this town to those of the neighboring town"
(synonym) total, tot, tot up, sum, sum up, summate, tote up, add together, tally, add up
(hypernym) count, number, enumerate, numerate
(verb-group) add together
(derivation) summation, addition, plus
constitute an addition; "This paper will add to her reputation"
(hypernym) form, constitute, make

现代英汉综合大辞典
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add
[æd]
vt.
加; 增添; 追加, 加算
接着又说, 补充说
合计, 累计
词性变化
add
[æd]
vi.
增加(to)
做加法
累积
得, 获
add fuel to the flame
火上加油
add insult to injury
凌辱交加; 进一步伤人感情
add (a) stone to one's cairn
人死后对他倍加推崇
Fireworks added to the attraction of the festival night.
焰火使节日的夜晚更加生色。
add
[æd]
n.
(一篇新闻报道的)后加部分
加法(运算)
a new add on the earthquake story
地震报道的新补充部分
继承用法
add-liser
n.
加算制表器
added
[ˈædɪd]
adj.
习惯用语
add in
算入; 包括
add on
加到上; 附加; 包括
add to
增加, 加到
add up
加起来, 总计; 和预期产总数相等; [口]有意义, 有道理
add up to
总计共达; (总起来看)等于说; 意味着
特殊用法
direct add
直接相加指令
false add
【计】无进位加
floating add
【计】浮点加
logical add
【计】逻辑加