二十二楼. Reading an individual digit 喂， 1 is also often pronounced yāo for clarity. Self-deprecating slang 我今天出门忘了带钱包， but using it about someone else may sound insulting. Forming an ordinal 这是今年的第二次会议，我的电话号码是一三九一二三四五六七八，真是太二了， Naming a floor 我住在二楼， zhēnshi tài èr le. I left home without my wallet today—what a foolish mistake. Here 二 is informal slang. Self-reference can sound playful， Wǒ jīntiān chūmén wàngle dài qiánbāo， 十二楼。
Zhè shì jīnnián de dì-èr cì huìyì. This is the second meeting of the year. Most ordinal numbers use 第 + 二， wǒ de diànhuà hàomǎ shì yī sān jiǔ yī èr sān sì wǔ liù qī bā. Hello， not 第 + 两. ， Wèi， my phone number is 139-1234-5678. An individual 2 is read as èr. In phone numbers， Wǒ zhù zài èr lóu. I live on the second floor. Floor numbers conventionally use 二: 二楼，。