He is merely throwing the idea forward for discussion, it is not cast in stone.

他只是抛出个想法供讨论，不是固定不变的。

《柯林斯英汉双解大词典》

Stop you move forward, not one hundred stone on the road of life, but that a pebble in your shoe.

阻止你前行的，不是人生道路上的一百块石头，而是你鞋子里的那一颗石子。

youdao

With a sigh and a click, a section of stone moved forward and then swung out, revealing a secret passage beyond.

随着一声叹息和滴答一声，一块石头向前移动了一段距离然后向外打开，露出一条秘密通向外面的通道。

youdao

"We've not thought beyond the World Cup, " insists the 5ft 10in, 14-stone Bristol forward.

BBC: England captain sacrifices all for World Cup glory bid

To be sure, the discovery of metallurgy was a huge leap forward in technology, but stone tools are sophisticated in design in their own right.

FORBES: The First Human Technology

Harinordoquy found 18-stone Bastareaud charging forward at his left shoulder and the 21-year-old evaded a desperate tackle by Kelly Brown to claim his second try of the game.

BBC: Scotland 9-18 France