stable, firm, steady, solid ☊ 
牢固 → ☊ 
vững chắc 
steady like: vững chắc → →
die Stabilität ☊ 
độ vững chắc ☊ 
☊ His arguments have a sound economic base. ☊ base ☊
disapprove sth: A solid majority disapproves the way the president is handling the controversy. ☊ disapprove ☊
These peaches are still firm. ☊ firm ☊
It was good to feel the firm ground underfoot after hours of trudging through flooded fields. ☊ firm ☊
Bake the cakes until they are firm to the touch. ☊ firm ☊
firm beliefs/conclusions/convictions/principles ☊ firm ☊
We have no firm evidence to support the case. ☊ firm ☊
Stand the fish tank on a firm base. ☊ firm ☊
No building can stand without firm foundations, and neither can a marriage. ☊ firm ☊
'No,' she repeated, her voice firmer this time. ☊ firm ☊
It is now firmly established as one of the leading brands in the country. ☊ firmly ☊
Keep your eyes firmly fixed on the road ahead. ☊ firmly ☊
Respect and friendship provide a solid foundation for marriage. ☊ foundation ☊
The company has adopted a firm policy on shoplifting. ☊ policy ☊
As yet, they have no solid evidence. ☊ solid ☊
His advice was always solid and practical. ☊ solid ☊
This provided a solid foundation for their marriage. ☊ solid ☊
These chains seem fairly solid. ☊ solid ☊
to have a steady relationship ☊ steady ☊
I met his steady gaze. ☊ steady ☊
This is an issue I feel strongly about (= I have firm opinions about). ☊ strongly ☊
She set the tone for the meeting with a firm statement of company policy. ☊ tone ☊
an unsteady hand ☊ unsteady ☊