You Make Me laugh

י  וַיֹּאמֶר, שׁוֹב אָשׁוּב אֵלֶיךָ כָּעֵת חַיָּה, וְהִנֵּה-בֵן, לְשָׂרָה אִשְׁתֶּךָ; וְשָׂרָה שֹׁמַעַת פֶּתַח הָאֹהֶל, וְהוּא אַחֲרָיו.

10
 And He said: 'I will certainly return unto thee when the season cometh round; and, lo, Sarah thy wife shall have a son.' And Sarah heard in the tent door, which was behind him.–

יא  וְאַבְרָהָם וְשָׂרָה זְקֵנִים, בָּאִים בַּיָּמִים; חָדַל לִהְיוֹת לְשָׂרָה, אֹרַח כַּנָּשִׁים.

11
 Now Abraham and Sarah were old, and well stricken in age; it had ceased to be with Sarah after the manner of women.–

יב  וַתִּצְחַק שָׂרָה, בְּקִרְבָּהּ לֵאמֹר:  אַחֲרֵי בְלֹתִי הָיְתָה-לִּי עֶדְנָה, וַאדֹנִי זָקֵן.

12
And Sarah laughed within herself, saying: 'After I am waxed old shall I have pleasure,
my lord being old also?'

יג  וַיֹּאמֶר יְהוָה, אֶל-אַבְרָהָם:  לָמָּה זֶּה צָחֲקָה שָׂרָה לֵאמֹר, הַאַף אֻמְנָם אֵלֵד–וַאֲנִי זָקַנְתִּי.

13
And the LORD said unto Abraham: 'Wherefore did Sarah laugh, saying:

Shall I of a surety bear a child,
?while I am old