a

英文解釋：

名詞 a:

1. a metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation
   同義詞：angstrom, angstrom unit
2. any of several fat-soluble vitamins essential for normal vision; prevents night blindness or inflammation or dryness of the eyes
   同義詞：vitamin A, antiophthalmic factor, axerophthol
3. one of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)
   同義詞：deoxyadenosine monophosphate
4. (biochemistry) purine base found in DNA and RNA; pairs with thymine in DNA and with uracil in RNA
   同義詞：adenine
5. the basic unit of electric current adopted under the Systeme International d'Unites
   同義詞：ampere, amp
6. the 1st letter of the Roman alphabet
   同義詞：letter a
7. the blood group whose red cells carry the A antigen
   同義詞：type A, group A

字典網

詞型變化：

相關對話：

1. I have engaged a room at this hotel.
   我已經在這個旅館裡預訂了一個房間。
2. You should give it a try.
   你應該試一試。
3. I don't care what a car looks like as long as it gets me from A to B.
   我倒不在乎汽車的樣子，只要能把我從一處載到另一處就行了。
4. The function of an adjective is to describe or add to the meaning of a noun.
   形容詞的作用是描述或增加名詞的意思。
5. China is a developing country.
   中國是一個開發中國家。
6. You're just a good for nothing bum!
   你一無是處！
7. Declension means varying the forms of nouns, pronouns and adjectives in a sentence.
   變格是指名詞、代詞和形容詞在句中的形式變化。
8. Would you do me a favor?
   你能幫我一個忙嗎？