TABLE 3.

T-test for the main four skills in pre- and post-test.

		Levene’s test for equality of variances		t-test for equality of means
		F	Sig.	T	df	Sig. (2-tailed)	95% Confidence interval of the difference
							Lower	Upper
Grammar. pre	Equal variances assumed	0.196	0.661	−0.625	41	0.536	−0.508	0.268
	Equal variances not assumed			−0.628	40.863	0.533	−0.505	0.265
Grammar. post	Equal variances assumed	2.046	0.160	−3.985	41	0.0003	−0.945	−0.309
	Equal variances not assumed			−3.885	33.096	0.0005	−0.955	−0.299