doukou，mortise of cap block
block and block [= chocka-block
bubble cap absorption column; bubble cap absorption tower
bubble cap bubbling cap
bubbling cap bubble cap
pile cap beam-less raft with post cap
2 atrioventricular block and complete atrioventricular block
BDCB Block Device Control Block
Block 36 and Block 38 in Oman
block by block relaxation operator
block by block transfer
block gage (gage block) (slip gage)
Block Xia 502 and Block Xia 509
block-by-block operation