door里oor发长元音，类似的还有：
1 awe [ɔː] [ɔ]
2 oar [ɔː] [ɔr]
3 or [ɔː] [ɔr]
4 ore [ɔː] [ɔr]
5 abnormal [æbˈnɔːml] [æbˈnɔrml]
6 aboard [əˈbɔːd] [əˈbɔrd]
7 abroad [əˈbrɔːd] [əˈbrɔd]
8 absorb [əbˈzɔːb -ˈsɔːb] [əbˈzɔb]
9 accord [əˈkɔːd] [əˈkɔrd]
10 accordance [əˈkɔːd(ə)ns] [əˈkɔrdns]
11 accordingly [əˈkɔːdɪŋlɪ] [əˈkɔrdɪŋli]
12 adore [əˈdɔː] [əˈdɔr]
13 afford [əˈfɔːd] [əˈfɔrd]
14 airport [ˈeəpɔːt] [ˈɛrˈpɔrt]
