make error /usr/bin/ld: cannot find -l boost_thread

[noobgrow]

CXX tools/upgrade_net_proto_binary.cpp CXX examples/rbox/deploy/librbox.cpp examples/rbox/deploy/librbox.cpp: In function ‘double Overlap(double*, double*)’: examples/rbox/deploy/librbox.cpp:567:7: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ examples/rbox/deploy/librbox.cpp: In function ‘void DecodeAndNMS(double*, double*, int*, double*, int*, double)’: examples/rbox/deploy/librbox.cpp:574:7: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ examples/rbox/deploy/librbox.cpp: In function ‘void NMS(double*, int*, double*, int*, double)’: examples/rbox/deploy/librbox.cpp:587:7: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ CXX .build_release/src/caffe/proto/caffe.pb.cc AR -o .build_release/lib/libcaffe.a LD -o .build_release/lib/libcaffe.so.1.0.0-rc3 /usr/bin/ld: cannot find -l　boost_thread collect2: error: ld returned 1 exit status Makefile:568: recipe for target '.build_release/lib/libcaffe.so.1.0.0-rc3' failed make: *** [.build_release/lib/libcaffe.so.1.0.0-rc3] Error 1
can u help me ?!!

I have libboost_thread.o in /usr/lib，but it still cant find it
I dont know how to fix it, anyone can help me ?
thanks a lot in advance!