Patients will be divided into two groups, arm A and arm B according to two different methods adopted in their first needle, which refers to the modified wet suction technique or 5ml dry suction technique.Take the solid occupying lesion diagnosis accuracy as the research major indicator to compare the the modified wet suction technique or 5ml dry suction technique as optimal efficiency test. Take classⅠerror, a=0.05, class II error, β=0.2, power=0.8, suppose that the diagnostic accuracy of dry suction technique to the solid occupying lesions is 75%, the diagnostic accuracy of modified wet suction technique to the solid occupying lesions is 85%, the minimum sample size are 248 patients with 5ml dry suction technique and 248 patients with modified wet suction technique, the 2x2 cross-over design is adopted, namely, each arm has 124 patients respectively. Considering factors including defluxion, 20% cases will be added to two arms, therefore, each arm has 148 patients respectively, the total number of patients is 296.