如何使用 Shift_R+Ctrl_R 作为第三行修改器？

Question

我买了一个奇怪的windozers键盘（Defender Oscar SM-600 PRO）。AltGr它有一个密钥，它发送和LNG的组合，而不是，并且它似乎不支持重新绑定它。Shift_RCtrl_R

xev按键时输出：

KeyPress event, serial 36, synthetic NO, window 0x4c00001,
    root 0x6cb, subw 0x0, time 321055557, (664,518), root:(666,520),
    state 0x10, keycode 105 (keysym 0xffe4, Control_R), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyPress event, serial 36, synthetic NO, window 0x4c00001,
    root 0x6cb, subw 0x0, time 321055557, (664,518), root:(666,520),
    state 0x14, keycode 62 (keysym 0xffe2, Shift_R), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyRelease event, serial 36, synthetic NO, window 0x4c00001,
    root 0x6cb, subw 0x0, time 321055670, (664,518), root:(666,520),
    state 0x15, keycode 105 (keysym 0xffe4, Control_R), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyRelease event, serial 36, synthetic NO, window 0x4c00001,
    root 0x6cb, subw 0x0, time 321055670, (664,518), root:(666,520),
    state 0x11, keycode 62 (keysym 0xffe2, Shift_R), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

如何制作Shift_R+Ctrl_R第三行修饰符，以便该键充当AltGr？理想情况下，还应该可以按Shift_L+ LNG( Shift_L++ Shift_R)Ctrl_R访问第四行。