不安bù ān
unpeaceful, unstable, uneasy不得了bù dé liǎo
desperately serious, disastrous不必bù bì
need not, does not have to不断bù duàn
unceasing, uninterrupted, continuous不耐烦bù nài fán
impatience, impatient不见得bù jiàn de
not necessarily, not likely不足bù zú
insufficient, lacking, deficiency专家zhuān jiā
expert, specialist