pollyanna：a person who is always cheerful and expects only good things to happen
positive：thinking about what is good in a situationfeeling confident and sure that sth good will happen
reserved：slow or unwilling to show feelings or express opinions
reticent：unwilling to tell people about things
self-conscious：nervous or embarrassed about your appearance or what ohter people think of you
shrinking voilet：a way of describing a very shy person
cociable：enjoying spending time whth other people
social butterfly：不知道
standoffish：not friendly towards other people
talk a blue streak：（自己译的）can't stop talking or speaking
timid：shy and nervous
upbeat：positive and unthusiastic
wallfower：a person who does not dance at a party beacuse they do not have sb to dance with or because they are too shy
whiny：annoying（自己译的）
纯手打,望采纳