Table 4. The results of CL and CTS based on empirical analysis.

	Dev		Test
Method	EM	F1	EM	F1
BERT base	65.70	–	64.70	–
BERT_empirical_CL	63.81	63.74	63.41	63.32
BERT_empirical_CTS	64.70	64.56	64.46	64.45